In systems that use communications servers to allow telephone devices and network telephone clients to make telephone calls through the communications servers, it can be beneficial to pass control and audio signals between a telephone network client and a telephone device. For example, this can allow user input commands from the network telephone client to control a call being made using a telephone device (e.g., putting the call on hold, etc.) and vice versa. Also, the passing of audio information may allow a call being made on a network telephone client to be continued on a telephone device and vice versa. This has been done using the universal serial bus (USB) protocol, where control messages have been passed in human interface device (HID) reports and audio information has been passed as USB audio information.